Wallace w



(No Mbdl.)

- W. W. D. JEPFERS;

PULP ENGINE.

No. 256,698. Patented Apr.18,18 82 a. 3 Fif 71661968, H

WW0? Q W N. PETERS, PhOXo-Lilhogmphnr, Washington. 0. C;

UNITED STATES PATENT Onnrcrz.

WALLACE VV. D. J EFFERS, OF TIOONDEROGA, NEW YORK.

PULP-ENGINE.

SPECIFICATION fOrming part of Letters Patent No. 256,698, dated April18, 188

Application filed March 15, 1882. (No model.)

To all whom it may concern:

Be it known that I, WALLACE W. D. JEF- FEES, of Ticonderoga, in thecounty of Essex, and in the State of New York, have invented certain newand useful Improvements in Pulp- Engines; and I do hereby declare thatthe following is a full, clear, and exact description thereof, referencebeing bad to the accompanying drawings, and to' the letters of referencemarked thereon, making a part of this specification.

This invention relates to" certain improvements in pulp-engines to beused for preparing stock for making paper in its various stages; and ithas for its object to provide certain means whereby thegrinding-surfaces may be made to wear uniformly, or as nearly uniformlythroughout their entire length from the inlet to the outlet openings, asmore fully hereinafter specified. In the engines of this class asheretofore, it has been found that the wear is the greatest at theoutlet end of the apparatus, at which portion the rotary grinder isgreater in diameter than at the other end, and consequently is subjectedto a greateramount of work; and my invention is designed to so constructthe grinding-surfaces that they will compensate for this unequal wear.These objects I attain by the apparatus illustrated in the accompanyingdrawings, in which- Figure 1 represents a longitudinal sectional view ofthe apparatus; Fig. 2, a transverse vertical sectional view of theapparatus, and Fig. 3 a diagram showing a modification of my invention.

The letter A indicates the outer shell, and B the inner shell or rotarygrinder, of the apparatus. These are each in the shape of a conoidalfrustum, the sides being curved in-- ward from the base to the smallerend, as clearly indicated in Fig.1 of the drawings. The inner surface ofthe shell-A and the outer surface of the grinder B are provided withlongitudinal corrugations a b, as shown, on workingsurfaces best adaptedto the stock which is to be manipulated and the paper made therefrom.

shell, the shaft also passing through suitable stuffing-boxes H.

The letter I indicates a screw at one end of the apparatus, bearingagainst the bolt K, the head of which is rounded and bears against thehead of a similar bolt, L, by means of which the grinder maybe adjustedwithin the shell. M is the driving-pulley of the shaft, and N a bearingfor the end of the shaft.

The letter P indicates the inlet and It the outlet pipe of theapparatus.

I am aware that pulping-engines have been grinder have been made each inthe form of a true frustum of a cone; but such machlnes are it is theintention of my invention to obviate. The difficulty with such enginesas formed end of the grinding-cone moves with greater velocity and thesurfaces come into more intimate contact by reason of the material beingmore finely reduced at the large end of the cone, thus causing thesurfaces to wear much more rapidly than at the smaller end.

By my method of constructing the machine it will be'perceived that theworking-surface of the grinder moves at a greater angle to thelongitudinal axis toward the outlet or large end than they move at theinlet or small end, the angle being gradually increased from the inletto the outlet, which construction permits the working parts toautomatically compensate for the unequal wear of the grinding-sue faces.

The apparatus may also be constructed of a series of conic frustums, asindicated in Fig. 3, with straight or curved sides, the sides of thesections being formed at varying angles with each other, as indicated,without departing from the spirit of my invention.

By my method of construction alarge amount of power is saved, owing tothe fact that the application of the working parts of the ma chine tothe stock-is such as to allow the stock comes distributed over thelarger surfaces more thoroughly worked in small bulk.

Having thus fully described my invention, what I claim, and desire tosecure by Letters Patent, is-- 1. In a pulping-engine, the outer shelland made in which the outer shell and inneropen to the objections aboveenumerated, which with conical grinding-surfaces is that the large to belightly worked at thest-art, and as it beinner grinder, constructed ofconoidal shape, with their walls inwardly curved from end to end,substantially as and for the purposes specified.

2, In a pulping-engine, the outer shell and inner grinder, formed ofconic sections of varying angles, substantially as and for the put posesspecified.

3. In a pulping-engine, the outer shell and x0 inner grinder or roll,constructed of conoidal shape, the longitudinal line of working-sur-

